This invention relates to the substrate of a member for recording information and a method of manufacturing the same. More particularly, it relates to the substrate of an information recording member employing a hard base of a material such as chemically reinforced glass, hard organic polymer and metal, and also to a method of manufacturing the same.
It is known from, for example, Japanese Published Unexamined Patent Application No. 55-4793 (corresponding to UK patent application GB 2,021,798) that the replica of groove-shaped and pit-shaped recesses for a servo track etc. is formed by the use of a light-curable resin such as ultraviolet-curing resin in the substrate of an information recording member for recording information with light. According to this method, an ultraviolet-curable resin layer is disposed on the surface of a mold, a base is arranged on the lacquer layer, ultraviolet rays are projected through the base or the mold thereby to cure the resin layer, the assembly which consists of the base and the resin layer cured to bond with the base is removed from the mold, and an information recording layer is thus formed on the resin layer side of the assembly. Regarding this method, however, facts as described below have been revealed. Since the ultraviolet-curing resin is hard to dissolve in an organic solvent after curing, it is difficult to remove the ultraviolet-curing resin which remains stuck on the mold, without having been removed with the base, at the removal of the assembly from the mold after the curing. Even when the amount of the resin which is left by one operation of forming the replica is slight, the resin accumulates when the mold is utilized for a plurality of operations of forming replicas, and errors in the case of reproducing the information increase. In addition, the stability of preservation for a long term is required of a recording film, which is therefore made of a material difficult to dissolve in acids, alkalies, water, organic solvents etc. Since both the substrate surface and the recording film are hard to dissolve in this manner, it is extremely difficult to dissolve the recording films of the recording members rejected in an inspection or the recording members used for reuse of the base.